While on the Big Island of Hawaii, we visited Volcano National Park. Calling this small amount of land a park is too modest; really the whole island – better yet, the whole state – should be the Volcano National Park, because it wouldn’t exist if it weren’t for the fact that it’s volcanic. And the Big Island is likely to grow significantly larger still. It’s made of five separate volcanoes that fused together as they developed. A sixth volcano – Loihi – sits 40km offshore and nearly a kilometre below sea level at the moment, but will pop out above water to form an island and then merge with the rest of the Big Island at some point in the next hundred millennia (in geological time, that’s the blink of an eye).
I always knew that the development of new volcanic land was an ongoing process, but before going to the Big Island I hadn’t appreciated the significance of this fact: Hawaiian volcanoes don’t go from a state of dormancy to eruption, because they erupt constantly. What changes is where and how much they erupt. The eruption in April this year wasn’t really an eruption, but an increased spurt of power and change of direction.
That extra spurt changed the course of the lava flow by 90o, and instead of flowing towards the sea, the lava now steers through private land and forests. We had hoped to see glowing red lava as it dropped into the ocean, but it’s not flowing that way at the moment. Short of trespassing, the only way to see the front end of the flow is by helicopter, and even then you can’t see anything because the helicopter flies too high. The lava’s working its way around trees, and it’s a slow process. The snail-like speed means the outside edge of the lava cools down quickly, resulting in only 2-3 inches of hot red lava tip. And that amount of boiling oozy stuff is so miniscule that it’s invisible from a helicopter. We’ll just have to return when the lava changes course back to the sea.
What we did see, that knocked our socks off, was an enormous, empty lava lake. It’s impossible to grasp the scale of this without a few numbers, so imagine this: a large vent, wide enough to fit two football pitches (soccer fields) side by side, that disappears deep into the centre of the earth. That vent sits below the level of the large Halema’uma’u Crater, which itself is half a mile across and deeper than the Statue of Liberty is tall. And the crater itself sits slightly off-centre in a huge, empty, three-mile wide caldera. Today, Kilauea caldera is empty, but 500 years ago it was full. Of lava. Lots and lots of it. Boiling, bubbling, burning. A huge lava lake three miles across.
Until April this year, the magma level in the crater’s vent was so low that it couldn’t be seen. However, April’s eleven-day “eruption” caused the lava to splash out of the vent onto the floor of Halema’uma’u Crater for the first time in 33 years. At the end of the eleven days the lava level subsided again, but the heat from the lava bubbling deep in the vent still lights up the steam at night. April’s eruption was exciting for those who were present to witness it, but the volume of lava was pitifully small compared with the amount that filled the lake 500 years ago. Then, it must have felt as if the earth had been turned inside out.
When you go to see the Kilauea Caldera on a clear night, you’re greeted by a vast plume of luminescent orange steam. You know the steam comes from an endless magma reservoir below the surface of the earth’s crust, and the steam does no more than hint at its immensity. As you follow the path of the steam towards the sky, you notice a myriad of stars in the firmament – significantly more than you’d see from your city home. And you observe: our world is colossal below, infinite above. We. Are. Tiny.